A manufacturing process of a semiconductor device may include manufacturing a series of semiconductor devices that make up a semiconductor apparatus. An assembly process may thereafter be performed.
Before such an assembly process is performed, a passivation layer may be formed, which may protect a semiconductor device from static electricity, moisture, impact, etc.
For example, such a passivation layer may play a role in protecting a semiconductor device from moisture, ultraviolet radiation from the sun, impact forces, pressure, and so forth.
A passivation layer may have a structure as illustrated in FIG. 1.
Referring to FIG. 1, a passivation layer may have a dual layer structure that may include lower passivation layer 120, for example made from silicon oxide, that may be formed on metal wiring 110. A passivation layer may also include upper passivation layer 130, for example made from silicon nitride. Metal wiring 110 may interconnect semiconductor devices.
An annealing process may be performed after laminating a passivation layer. During an annealing process, fumes (e.g. gases) may occur from the lower layer of the passivation layer. In a dual layer passivation layer structure, a passivation layer may not be able to bear the pressure of the fume gas. In this situation, the silicon nitride layer (upper layer 130) may be partially removed from the silicon oxide layer (lower layer 120). Therefore, failure 180 may occur as illustrated in FIG. 1.
Hence, a general passivation layer having a dual layer structure may include a silicon oxide layer and a silicon nitride layer. In the passivation layer with the dual layer structure, upper layer 130 and lower layer 120 may have a large surface stress difference therebetween and may have poor adhesive strength therebetween. Therefore, upper passivation layer 130 may become partially removed from lower passivation layer 120, for example in a high temperature process such as an annealing process. Moreover, if upper passivation layer 130 is damaged, a semiconductor device may be damaged by chemical materials in a subsequent packaging process.
A failure of the passivation layer may cause a semiconductor device to be damaged by chemical materials used in a subsequent assembly process, and may cause other failures to occur, for example failures in a wire bonding process.